Updates in the Management of Clostridium Difficile for Adults

Kimberly E. Ng, PharmD, BCPS


US Pharmacist. 2019;44(4):HS9-HS12. 

In This Article


Fidaxomicin (Dificid) is a macrolide antibacterial drug that is bactericidal against C difficile in vitro, inhibiting RNA synthesis by RNA polymerases; it was approved in May 2011. It is indicated for adults aged 18 years and older for the treatment of C difficile–associated diarrhea. To reduce drug-resistant bacteria and maintain effectiveness, fidaxomicin should only be used to treat infections that are either proven or strongly suspected to be caused by C difficile. The recommended dose is 200 mg orally twice daily for 10 days with or without food.

FDA approval was based on two randomized, double-blind, noninferiority trials that compared fidaxomicin with vancomycin. The primary outcomes were clinical response rate at the end of therapy based on improvement in diarrhea or other symptoms and sustained clinical response 25 days after the end of treatment. Both endpoints were achieved to show that fidaxomicin is noninferior to vancomycin. Reported adverse events include nausea, vomiting, abdominal pain, gastrointestinal hemorrhage, anemia, and neutropenia.[8,9]